linux-toradex.git/include/linux, branch v4.4.117 Linux kernel for Apalis and Colibri modules x86: fix build warnign with 32-bit PAE 2018-02-22T14:45:01+00:00 Arnd Bergmann arnd@arndb.de 2018-02-15T15:16:57+00:00 4b35dcb5e048cde1a68603d5ad2d8ccaf3fb1e4e I ran into a 4.9 build warning in randconfig testing, starting with the KAISER patches: arch/x86/kernel/ldt.c: In function 'alloc_ldt_struct': arch/x86/include/asm/pgtable_types.h:208:24: error: large integer implicitly truncated to unsigned type [-Werror=overflow] #define __PAGE_KERNEL (__PAGE_KERNEL_EXEC | _PAGE_NX) ^ arch/x86/kernel/ldt.c:81:6: note: in expansion of macro '__PAGE_KERNEL' __PAGE_KERNEL); ^~~~~~~~~~~~~ I originally ran into this last year when the patches were part of linux-next, and tried to work around it by using the proper 'pteval_t' types consistently, but that caused additional problems. This takes a much simpler approach, and makes the argument type of the dummy helper always 64-bit, which is wide enough for any page table layout and won't hurt since this call is just an empty stub anyway. Fixes: 8f0baadf2bea ("kaiser: merged update") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
I ran into a 4.9 build warning in randconfig testing, starting with the
KAISER patches:

arch/x86/kernel/ldt.c: In function 'alloc_ldt_struct':
arch/x86/include/asm/pgtable_types.h:208:24: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
 #define __PAGE_KERNEL  (__PAGE_KERNEL_EXEC | _PAGE_NX)
                        ^
arch/x86/kernel/ldt.c:81:6: note: in expansion of macro '__PAGE_KERNEL'
      __PAGE_KERNEL);
      ^~~~~~~~~~~~~

I originally ran into this last year when the patches were part of linux-next,
and tried to work around it by using the proper 'pteval_t' types consistently,
but that caused additional problems.

This takes a much simpler approach, and makes the argument type of the dummy
helper always 64-bit, which is wide enough for any page table layout and
won't hurt since this call is just an empty stub anyway.

Fixes: 8f0baadf2bea ("kaiser: merged update")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mtd: cfi: convert inline functions to macros 2018-02-16T19:09:41+00:00 Arnd Bergmann arnd@arndb.de 2017-10-11T13:54:10+00:00 b4b3ad0c8c90b4a9fe1dc9ecca9211a72e580976 commit 9e343e87d2c4c707ef8fae2844864d4dde3a2d13 upstream. The map_word_() functions, dating back to linux-2.6.8, try to perform bitwise operations on a 'map_word' structure. This may have worked with compilers that were current then (gcc-3.4 or earlier), but end up being rather inefficient on any version I could try now (gcc-4.4 or higher). Specifically we hit a problem analyzed in gcc PR81715 where we fail to reuse the stack space for local variables. This can be seen immediately in the stack consumption for cfi_staa_erase_varsize() and other functions that (with CONFIG_KASAN) can be up to 2200 bytes. Changing the inline functions into macros brings this down to 1280 bytes. Without KASAN, the same problem exists, but the stack consumption is lower to start with, my patch shrinks it from 920 to 496 bytes on with arm-linux-gnueabi-gcc-5.4, and saves around 1KB in .text size for cfi_cmdset_0020.c, as it avoids copying map_word structures for each call to one of these helpers. With the latest gcc-8 snapshot, the problem is fixed in upstream gcc, but nobody uses that yet, so we should still work around it in mainline kernels and probably backport the workaround to stable kernels as well. We had a couple of other functions that suffered from the same gcc bug, and all of those had a simpler workaround involving dummy variables in the inline function. Unfortunately that did not work here, the macro hack was the best I could come up with. It would also be helpful to have someone to a little performance testing on the patch, to see how much it helps in terms of CPU utilitzation. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Richard Weinberger <richard@nod.at> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9e343e87d2c4c707ef8fae2844864d4dde3a2d13 upstream.

The map_word_() functions, dating back to linux-2.6.8, try to perform
bitwise operations on a 'map_word' structure. This may have worked
with compilers that were current then (gcc-3.4 or earlier), but end
up being rather inefficient on any version I could try now (gcc-4.4 or
higher). Specifically we hit a problem analyzed in gcc PR81715 where we
fail to reuse the stack space for local variables.

This can be seen immediately in the stack consumption for
cfi_staa_erase_varsize() and other functions that (with CONFIG_KASAN)
can be up to 2200 bytes. Changing the inline functions into macros brings
this down to 1280 bytes.  Without KASAN, the same problem exists, but
the stack consumption is lower to start with, my patch shrinks it from
920 to 496 bytes on with arm-linux-gnueabi-gcc-5.4, and saves around
1KB in .text size for cfi_cmdset_0020.c, as it avoids copying map_word
structures for each call to one of these helpers.

With the latest gcc-8 snapshot, the problem is fixed in upstream gcc,
but nobody uses that yet, so we should still work around it in mainline
kernels and probably backport the workaround to stable kernels as well.
We had a couple of other functions that suffered from the same gcc bug,
and all of those had a simpler workaround involving dummy variables
in the inline function. Unfortunately that did not work here, the
macro hack was the best I could come up with.

It would also be helpful to have someone to a little performance testing
on the patch, to see how much it helps in terms of CPU utilitzation.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
don't put symlink bodies in pagecache into highmem 2018-02-16T19:09:38+00:00 Al Viro viro@zeniv.linux.org.uk 2015-11-17T06:07:57+00:00 076e4ab3279eb3ddb206de44d04df7aeb2428e09 commit 21fc61c73c3903c4c312d0802da01ec2b323d174 upstream. kmap() in page_follow_link_light() needed to go - allowing to hold an arbitrary number of kmaps for long is a great way to deadlocking the system. new helper (inode_nohighmem(inode)) needs to be used for pagecache symlinks inodes; done for all in-tree cases. page_follow_link_light() instrumented to yell about anything missed. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jin Qian <jinqian@google.com> Signed-off-by: Jin Qian <jinqian@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 21fc61c73c3903c4c312d0802da01ec2b323d174 upstream.

kmap() in page_follow_link_light() needed to go - allowing to hold
an arbitrary number of kmaps for long is a great way to deadlocking
the system.

new helper (inode_nohighmem(inode)) needs to be used for pagecache
symlinks inodes; done for all in-tree cases.  page_follow_link_light()
instrumented to yell about anything missed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jin Qian <jinqian@google.com>
Signed-off-by: Jin Qian <jinqian@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bpf: avoid false sharing of map refcount with max_entries 2018-02-03T16:04:24+00:00 Daniel Borkmann daniel@iogearbox.net 2018-01-30T02:37:43+00:00 96d9b2338bed553c37f759127d8d18c857449ceb [ upstream commit be95a845cc4402272994ce290e3ad928aff06cb9 ] In addition to commit b2157399cc98 ("bpf: prevent out-of-bounds speculation") also change the layout of struct bpf_map such that false sharing of fast-path members like max_entries is avoided when the maps reference counter is altered. Therefore enforce them to be placed into separate cachelines. pahole dump after change: struct bpf_map { const struct bpf_map_ops * ops; /* 0 8 */ struct bpf_map * inner_map_meta; /* 8 8 */ void * security; /* 16 8 */ enum bpf_map_type map_type; /* 24 4 */ u32 key_size; /* 28 4 */ u32 value_size; /* 32 4 */ u32 max_entries; /* 36 4 */ u32 map_flags; /* 40 4 */ u32 pages; /* 44 4 */ u32 id; /* 48 4 */ int numa_node; /* 52 4 */ bool unpriv_array; /* 56 1 */ /* XXX 7 bytes hole, try to pack */ /* --- cacheline 1 boundary (64 bytes) --- */ struct user_struct * user; /* 64 8 */ atomic_t refcnt; /* 72 4 */ atomic_t usercnt; /* 76 4 */ struct work_struct work; /* 80 32 */ char name[16]; /* 112 16 */ /* --- cacheline 2 boundary (128 bytes) --- */ /* size: 128, cachelines: 2, members: 17 */ /* sum members: 121, holes: 1, sum holes: 7 */ }; Now all entries in the first cacheline are read only throughout the life time of the map, set up once during map creation. Overall struct size and number of cachelines doesn't change from the reordering. struct bpf_map is usually first member and embedded in map structs in specific map implementations, so also avoid those members to sit at the end where it could potentially share the cacheline with first map values e.g. in the array since remote CPUs could trigger map updates just as well for those (easily dirtying members like max_entries intentionally as well) while having subsequent values in cache. Quoting from Google's Project Zero blog [1]: Additionally, at least on the Intel machine on which this was tested, bouncing modified cache lines between cores is slow, apparently because the MESI protocol is used for cache coherence [8]. Changing the reference counter of an eBPF array on one physical CPU core causes the cache line containing the reference counter to be bounced over to that CPU core, making reads of the reference counter on all other CPU cores slow until the changed reference counter has been written back to memory. Because the length and the reference counter of an eBPF array are stored in the same cache line, this also means that changing the reference counter on one physical CPU core causes reads of the eBPF array's length to be slow on other physical CPU cores (intentional false sharing). While this doesn't 'control' the out-of-bounds speculation through masking the index as in commit b2157399cc98, triggering a manipulation of the map's reference counter is really trivial, so lets not allow to easily affect max_entries from it. Splitting to separate cachelines also generally makes sense from a performance perspective anyway in that fast-path won't have a cache miss if the map gets pinned, reused in other progs, etc out of control path, thus also avoids unintentional false sharing. [1] https://googleprojectzero.blogspot.ch/2018/01/reading-privileged-memory-with-side.html Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ upstream commit be95a845cc4402272994ce290e3ad928aff06cb9 ]

In addition to commit b2157399cc98 ("bpf: prevent out-of-bounds
speculation") also change the layout of struct bpf_map such that
false sharing of fast-path members like max_entries is avoided
when the maps reference counter is altered. Therefore enforce
them to be placed into separate cachelines.

pahole dump after change:

  struct bpf_map {
        const struct bpf_map_ops  * ops;                 /*     0     8 */
        struct bpf_map *           inner_map_meta;       /*     8     8 */
        void *                     security;             /*    16     8 */
        enum bpf_map_type          map_type;             /*    24     4 */
        u32                        key_size;             /*    28     4 */
        u32                        value_size;           /*    32     4 */
        u32                        max_entries;          /*    36     4 */
        u32                        map_flags;            /*    40     4 */
        u32                        pages;                /*    44     4 */
        u32                        id;                   /*    48     4 */
        int                        numa_node;            /*    52     4 */
        bool                       unpriv_array;         /*    56     1 */

        /* XXX 7 bytes hole, try to pack */

        /* --- cacheline 1 boundary (64 bytes) --- */
        struct user_struct *       user;                 /*    64     8 */
        atomic_t                   refcnt;               /*    72     4 */
        atomic_t                   usercnt;              /*    76     4 */
        struct work_struct         work;                 /*    80    32 */
        char                       name[16];             /*   112    16 */
        /* --- cacheline 2 boundary (128 bytes) --- */

        /* size: 128, cachelines: 2, members: 17 */
        /* sum members: 121, holes: 1, sum holes: 7 */
  };

Now all entries in the first cacheline are read only throughout
the life time of the map, set up once during map creation. Overall
struct size and number of cachelines doesn't change from the
reordering. struct bpf_map is usually first member and embedded
in map structs in specific map implementations, so also avoid those
members to sit at the end where it could potentially share the
cacheline with first map values e.g. in the array since remote
CPUs could trigger map updates just as well for those (easily
dirtying members like max_entries intentionally as well) while
having subsequent values in cache.

Quoting from Google's Project Zero blog [1]:

  Additionally, at least on the Intel machine on which this was
  tested, bouncing modified cache lines between cores is slow,
  apparently because the MESI protocol is used for cache coherence
  [8]. Changing the reference counter of an eBPF array on one
  physical CPU core causes the cache line containing the reference
  counter to be bounced over to that CPU core, making reads of the
  reference counter on all other CPU cores slow until the changed
  reference counter has been written back to memory. Because the
  length and the reference counter of an eBPF array are stored in
  the same cache line, this also means that changing the reference
  counter on one physical CPU core causes reads of the eBPF array's
  length to be slow on other physical CPU cores (intentional false
  sharing).

While this doesn't 'control' the out-of-bounds speculation through
masking the index as in commit b2157399cc98, triggering a manipulation
of the map's reference counter is really trivial, so lets not allow
to easily affect max_entries from it.

Splitting to separate cachelines also generally makes sense from
a performance perspective anyway in that fast-path won't have a
cache miss if the map gets pinned, reused in other progs, etc out
of control path, thus also avoids unintentional false sharing.

  [1] https://googleprojectzero.blogspot.ch/2018/01/reading-privileged-memory-with-side.html

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp: __tcp_hdrlen() helper 2018-01-31T11:06:13+00:00 Craig Gallek kraig@google.com 2016-02-10T16:50:37+00:00 bed42ef5ebbfc046e0440f7e0f941cc07f8ca1e8 commit d9b3fca27385eafe61c3ca6feab6cb1e7dc77482 upstream. tcp_hdrlen is wasteful if you already have a pointer to struct tcphdr. This splits the size calculation into a helper function that can be used if a struct tcphdr is already available. Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit d9b3fca27385eafe61c3ca6feab6cb1e7dc77482 upstream.

tcp_hdrlen is wasteful if you already have a pointer to struct tcphdr.
This splits the size calculation into a helper function that can be
used if a struct tcphdr is already available.

Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "module: Add retpoline tag to VERMAGIC" 2018-01-31T11:06:11+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2018-01-24T14:28:17+00:00 5f1dc06152e1683a9277a2836517d6574757dd1f commit 5132ede0fe8092b043dae09a7cc32b8ae7272baa upstream. This reverts commit 6cfb521ac0d5b97470883ff9b7facae264b7ab12. Turns out distros do not want to make retpoline as part of their "ABI", so this patch should not have been merged. Sorry Andi, this was my fault, I suggested it when your original patch was the "correct" way of doing this instead. Reported-by: Jiri Kosina <jikos@kernel.org> Fixes: 6cfb521ac0d5 ("module: Add retpoline tag to VERMAGIC") Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: rusty@rustcorp.com.au Cc: arjan.van.de.ven@intel.com Cc: jeyu@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5132ede0fe8092b043dae09a7cc32b8ae7272baa upstream.

This reverts commit 6cfb521ac0d5b97470883ff9b7facae264b7ab12.

Turns out distros do not want to make retpoline as part of their "ABI",
so this patch should not have been merged.  Sorry Andi, this was my
fault, I suggested it when your original patch was the "correct" way of
doing this instead.

Reported-by: Jiri Kosina <jikos@kernel.org>
Fixes: 6cfb521ac0d5 ("module: Add retpoline tag to VERMAGIC")
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: rusty@rustcorp.com.au
Cc: arjan.van.de.ven@intel.com
Cc: jeyu@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
netfilter: fix IS_ERR_VALUE usage 2018-01-31T11:06:10+00:00 Pablo Neira Ayuso pablo@netfilter.org 2016-04-29T08:39:34+00:00 936b21419e7c5be2f81e6dea02fc3d8852f3fb83 commit 92b4423e3a0bc5d43ecde4bcad871f8b5ba04efd upstream. This is a forward-port of the original patch from Andrzej Hajda, he said: "IS_ERR_VALUE should be used only with unsigned long type. Otherwise it can work incorrectly. To achieve this function xt_percpu_counter_alloc is modified to return unsigned long, and its result is assigned to temporary variable to perform error checking, before assigning to .pcnt field. The patch follows conclusion from discussion on LKML [1][2]. [1]: http://permalink.gmane.org/gmane.linux.kernel/2120927 [2]: http://permalink.gmane.org/gmane.linux.kernel/2150581" Original patch from Andrzej is here: http://patchwork.ozlabs.org/patch/582970/ This patch has clashed with input validation fixes for x_tables. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Michal Kubecek <mkubecek@suse.cz> 
commit 92b4423e3a0bc5d43ecde4bcad871f8b5ba04efd upstream.

This is a forward-port of the original patch from Andrzej Hajda,
he said:

"IS_ERR_VALUE should be used only with unsigned long type.
Otherwise it can work incorrectly. To achieve this function
xt_percpu_counter_alloc is modified to return unsigned long,
and its result is assigned to temporary variable to perform
error checking, before assigning to .pcnt field.

The patch follows conclusion from discussion on LKML [1][2].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2120927
[2]: http://permalink.gmane.org/gmane.linux.kernel/2150581"

Original patch from Andrzej is here:

http://patchwork.ozlabs.org/patch/582970/

This patch has clashed with input validation fixes for x_tables.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Michal Kubecek <mkubecek@suse.cz>
netfilter: x_tables: speed up jump target validation 2018-01-31T11:06:10+00:00 Florian Westphal fw@strlen.de 2016-07-14T15:51:26+00:00 45cf54e13c70ce0ec4875220103916978ce3ed07 commit f4dc77713f8016d2e8a3295e1c9c53a21f296def upstream. The dummy ruleset I used to test the original validation change was broken, most rules were unreachable and were not tested by mark_source_chains(). In some cases rulesets that used to load in a few seconds now require several minutes. sample ruleset that shows the behaviour: echo "*filter" for i in $(seq 0 100000);do printf ":chain_%06x - [0:0]\n" $i done for i in $(seq 0 100000);do printf -- "-A INPUT -j chain_%06x\n" $i printf -- "-A INPUT -j chain_%06x\n" $i printf -- "-A INPUT -j chain_%06x\n" $i done echo COMMIT [ pipe result into iptables-restore ] This ruleset will be about 74mbyte in size, with ~500k searches though all 500k[1] rule entries. iptables-restore will take forever (gave up after 10 minutes) Instead of always searching the entire blob for a match, fill an array with the start offsets of every single ipt_entry struct, then do a binary search to check if the jump target is present or not. After this change ruleset restore times get again close to what one gets when reverting 36472341017529e (~3 seconds on my workstation). [1] every user-defined rule gets an implicit RETURN, so we get 300k jumps + 100k userchains + 100k returns -> 500k rule entries Fixes: 36472341017529e ("netfilter: x_tables: validate targets of jumps") Reported-by: Jeff Wu <wujiafu@gmail.com> Tested-by: Jeff Wu <wujiafu@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f4dc77713f8016d2e8a3295e1c9c53a21f296def upstream.

The dummy ruleset I used to test the original validation change was broken,
most rules were unreachable and were not tested by mark_source_chains().

In some cases rulesets that used to load in a few seconds now require
several minutes.

sample ruleset that shows the behaviour:

echo "*filter"
for i in $(seq 0 100000);do
        printf ":chain_%06x - [0:0]\n" $i
done
for i in $(seq 0 100000);do
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
done
echo COMMIT

[ pipe result into iptables-restore ]

This ruleset will be about 74mbyte in size, with ~500k searches
though all 500k[1] rule entries. iptables-restore will take forever
(gave up after 10 minutes)

Instead of always searching the entire blob for a match, fill an
array with the start offsets of every single ipt_entry struct,
then do a binary search to check if the jump target is present or not.

After this change ruleset restore times get again close to what one
gets when reverting 36472341017529e (~3 seconds on my workstation).

[1] every user-defined rule gets an implicit RETURN, so we get
300k jumps + 100k userchains + 100k returns -> 500k rule entries

Fixes: 36472341017529e ("netfilter: x_tables: validate targets of jumps")
Reported-by: Jeff Wu <wujiafu@gmail.com>
Tested-by: Jeff Wu <wujiafu@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers: base: cacheinfo: fix x86 with CONFIG_OF enabled 2018-01-31T11:06:08+00:00 Sudeep Holla sudeep.holla@arm.com 2016-10-28T08:45:28+00:00 f31a8450c09327339939fe195707749c1d67016d commit fac51482577d5e05bbb0efa8d602a3c2111098bf upstream. With CONFIG_OF enabled on x86, we get the following error on boot: " Failed to find cpu0 device node Unable to detect cache hierarchy from DT for CPU 0 " and the cacheinfo fails to get populated in the corresponding sysfs entries. This is because cache_setup_of_node looks for of_node for setting up the shared cpu_map without checking that it's already populated in the architecture specific callback. In order to indicate that the shared cpu_map is already populated, this patch introduces a boolean `cpu_map_populated` in struct cpu_cacheinfo that can be used by the generic code to skip cache_shared_cpu_map_setup. This patch also sets that boolean for x86. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fac51482577d5e05bbb0efa8d602a3c2111098bf upstream.

With CONFIG_OF enabled on x86, we get the following error on boot:
"
	Failed to find cpu0 device node
 	Unable to detect cache hierarchy from DT for CPU 0
"
and the cacheinfo fails to get populated in the corresponding sysfs
entries. This is because cache_setup_of_node looks for of_node for
setting up the shared cpu_map without checking that it's already
populated in the architecture specific callback.

In order to indicate that the shared cpu_map is already populated, this
patch introduces a boolean `cpu_map_populated` in struct cpu_cacheinfo
that can be used by the generic code to skip cache_shared_cpu_map_setup.

This patch also sets that boolean for x86.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
time: Avoid undefined behaviour in ktime_add_safe() 2018-01-31T11:06:08+00:00 Vegard Nossum vegard.nossum@oracle.com 2016-08-12T23:37:04+00:00 08b1cf4964d526cf3c2ea9e36ffd752752543ef3 commit 979515c5645830465739254abc1b1648ada41518 upstream. I ran into this: ================================================================================ UBSAN: Undefined behaviour in kernel/time/hrtimer.c:310:16 signed integer overflow: 9223372036854775807 + 50000 cannot be represented in type 'long long int' CPU: 2 PID: 4798 Comm: trinity-c2 Not tainted 4.8.0-rc1+ #91 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 0000000000000000 ffff88010ce6fb88 ffffffff82344740 0000000041b58ab3 ffffffff84f97a20 ffffffff82344694 ffff88010ce6fbb0 ffff88010ce6fb60 000000000000c350 ffff88010ce6f968 dffffc0000000000 ffffffff857bc320 Call Trace: [<ffffffff82344740>] dump_stack+0xac/0xfc [<ffffffff82344694>] ? _atomic_dec_and_lock+0xc4/0xc4 [<ffffffff8242df78>] ubsan_epilogue+0xd/0x8a [<ffffffff8242e6b4>] handle_overflow+0x202/0x23d [<ffffffff8242e4b2>] ? val_to_string.constprop.6+0x11e/0x11e [<ffffffff8236df71>] ? timerqueue_add+0x151/0x410 [<ffffffff81485c48>] ? hrtimer_start_range_ns+0x3b8/0x1380 [<ffffffff81795631>] ? memset+0x31/0x40 [<ffffffff8242e6fd>] __ubsan_handle_add_overflow+0xe/0x10 [<ffffffff81488ac9>] hrtimer_nanosleep+0x5d9/0x790 [<ffffffff814884f0>] ? hrtimer_init_sleeper+0x80/0x80 [<ffffffff813a9ffb>] ? __might_sleep+0x5b/0x260 [<ffffffff8148be10>] common_nsleep+0x20/0x30 [<ffffffff814906c7>] SyS_clock_nanosleep+0x197/0x210 [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150 [<ffffffff823c7113>] ? __this_cpu_preempt_check+0x13/0x20 [<ffffffff8162ef60>] ? __context_tracking_exit.part.3+0x30/0x1b0 [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150 [<ffffffff81007bd3>] do_syscall_64+0x1b3/0x4b0 [<ffffffff845f85aa>] entry_SYSCALL64_slow_path+0x25/0x25 ================================================================================ Add a new ktime_add_unsafe() helper which doesn't check for overflow, but doesn't throw a UBSAN warning when it does overflow either. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 979515c5645830465739254abc1b1648ada41518 upstream.

I ran into this:

    ================================================================================
    UBSAN: Undefined behaviour in kernel/time/hrtimer.c:310:16
    signed integer overflow:
    9223372036854775807 + 50000 cannot be represented in type 'long long int'
    CPU: 2 PID: 4798 Comm: trinity-c2 Not tainted 4.8.0-rc1+ #91
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
     0000000000000000 ffff88010ce6fb88 ffffffff82344740 0000000041b58ab3
     ffffffff84f97a20 ffffffff82344694 ffff88010ce6fbb0 ffff88010ce6fb60
     000000000000c350 ffff88010ce6f968 dffffc0000000000 ffffffff857bc320
    Call Trace:
     [<ffffffff82344740>] dump_stack+0xac/0xfc
     [<ffffffff82344694>] ? _atomic_dec_and_lock+0xc4/0xc4
     [<ffffffff8242df78>] ubsan_epilogue+0xd/0x8a
     [<ffffffff8242e6b4>] handle_overflow+0x202/0x23d
     [<ffffffff8242e4b2>] ? val_to_string.constprop.6+0x11e/0x11e
     [<ffffffff8236df71>] ? timerqueue_add+0x151/0x410
     [<ffffffff81485c48>] ? hrtimer_start_range_ns+0x3b8/0x1380
     [<ffffffff81795631>] ? memset+0x31/0x40
     [<ffffffff8242e6fd>] __ubsan_handle_add_overflow+0xe/0x10
     [<ffffffff81488ac9>] hrtimer_nanosleep+0x5d9/0x790
     [<ffffffff814884f0>] ? hrtimer_init_sleeper+0x80/0x80
     [<ffffffff813a9ffb>] ? __might_sleep+0x5b/0x260
     [<ffffffff8148be10>] common_nsleep+0x20/0x30
     [<ffffffff814906c7>] SyS_clock_nanosleep+0x197/0x210
     [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150
     [<ffffffff823c7113>] ? __this_cpu_preempt_check+0x13/0x20
     [<ffffffff8162ef60>] ? __context_tracking_exit.part.3+0x30/0x1b0
     [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150
     [<ffffffff81007bd3>] do_syscall_64+0x1b3/0x4b0
     [<ffffffff845f85aa>] entry_SYSCALL64_slow_path+0x25/0x25
    ================================================================================

Add a new ktime_add_unsafe() helper which doesn't check for overflow, but
doesn't throw a UBSAN warning when it does overflow either.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>